Turbo compressor and turbo refrigerator

ABSTRACT

A turbo compressor according to the present invention includes: a flow rate adjustment section which adjusts the flow rate of gas that is introduced into an impeller; a driving section which drives the flow rate adjustment section; and a power transmission shaft which transmits power that is generated by the driving section to the flow rate adjustment section, wherein the turbo compressor further includes a frame which is provided to surround the flow rate adjustment section, and the frame has an intake port for gas that is introduced into the impeller and a hole portion in which the power transmission shaft is provided passing through.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a turbo compressor and a turbo refrigerator. Priority is claimed on Japanese Patent Application No. 2010-053737, filed on Mar. 10, 2010, the contents of which are incorporated herein by reference.

2. Description of Related Art

As a refrigerator which cools or refrigerates a cooling object such as water or the like, a turbo refrigerator which is provided with a turbo compressor that compresses and discharges refrigerant gas is known. In the turbo compressor of such a turbo refrigerator, there is a case where a flow rate adjustment unit that adjusts the flow rate of the refrigerant gas that is introduced into a rotating impeller is provided, as shown in, for example, Japanese Unexamined Patent Application Publication No. 2007-177695. It is possible to adjust the compression performance of the turbo compressor and the cooling and refrigeration performance or the like of the turbo refrigerator by adjusting the flow rate of the refrigerant gas by the flow rate adjustment unit. The flow rate adjustment unit includes a flow rate adjustment section which is provided with a plurality of vanes (blades), a driving section such as a motor or the like which drives the flow rate adjustment section, and a power transmission shaft which transmits power that is generated by the driving section to the flow rate adjustment section.

SUMMARY OF THE INVENTION

Incidentally, the power transmission shaft is provided passing through a hole portion which is formed in a casing of the turbo compressor, and connects the flow rate adjustment section and the driving section, which are respectively provided inside and outside the casing. In the case of assembling the flow rate adjustment section and the power transmission shaft, it is necessary to first install the flow rate adjustment section in the inside of the casing and then connect the power transmission shaft to the flow rate adjustment section by passing the power transmission shaft through the hole portion.

However, since a connection place of the flow rate adjustment section installed inside the casing and the power transmission shaft cannot be checked from the outside, work to assemble the flow rate adjustment section and the power transmission shaft is difficult, so that the assembly workability is lowered. As a result, the labor hours and cost involved in the manufacturing of the turbo compressor and the turbo refrigerator, which are provided with the flow rate adjustment section and the power transmission shaft, increase.

The present invention has been made in consideration of the circumstances as mentioned above and has an object of providing a turbo compressor and a turbo refrigerator, which improve the assembly workability of a flow rate adjustment section and a power transmission shaft, thereby allowing, the labor hours and cost of the manufacturing to be reduced.

In order to solve the above-mentioned problems, the present invention adopts the following means.

A turbo compressor according to a first aspect of the present invention includes: a flow rate adjustment section which adjusts the flow rate of gas that is introduced into an impeller; a driving section which drives the flow rate adjustment section; and a power transmission shaft which transmits power that is generated by the driving section to the flow rate adjustment section, wherein the turbo compressor further includes a frame which is provided to surround the flow rate adjustment section, and the frame has an intake port for gas that is introduced into the impeller and a hole portion in which the power transmission shaft is provided passing through.

According to the first aspect of the present invention, the power transmission shaft is provided passing through the hole portion which is formed in the frame, and connects the flow rate adjustment section and the driving section, which are respectively provided inside and outside the frame. In the case of assembling the flow rate adjustment section and the power transmission shaft, before the frame is fixed to a casing of the turbo compressor, the power transmission shaft is connected to the flow rate adjustment section by passing the power transmission shaft through the hole portion of the frame. That is, it is possible to assemble the flow rate adjustment section and the power transmission shaft while checking a connection place of the flow rate adjustment section and the power transmission shaft from the outside, so that the assembly workability of the flow rate adjustment section and the power transmission shaft is improved.

Also, in the turbo compressor according to a second aspect of the present invention, the frame is provided in an annular shape to surround the flow rate adjustment section and has an outer diameter which is reduced as it becomes more distant from the impeller.

Also, the turbo compressor according to a third aspect of the present invention further includes a connection section which connects an output shaft which outputs the power of the driving section and the power transmission shaft.

Also, the turbo compressor according to a fourth aspect of the present invention further includes a seal member which keeps the hole portion, in which the power transmission shaft is provided passing through, in an airtight manner.

Also, a turbo refrigerator according to a fifth aspect of the present invention includes: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to any one of the first to fourth aspects of the present invention as the compressor.

According to the present invention, the following effects can be obtained.

According to the present invention, it is possible to assemble the flow rate adjustment section and the power transmission shaft while checking a connection place of the flow rate adjustment section and the power transmission shaft from the outside, so that the assembly workability of the flow rate adjustment section and the power transmission shaft is improved. Accordingly, the labor hours and cost involved in the manufacturing of the turbo compressor and the turbo refrigerator, each of which is provided with the flow rate adjustment section and the power transmission shaft, can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a schematic configuration of a turbo refrigerator related to an embodiment of the present invention.

FIG. 2 is a horizontal cross-sectional view of a turbo compressor related to the embodiment of the present invention.

FIG. 3 is a horizontal cross-sectional view of a flow rate adjustment unit related to the embodiment of the present invention.

FIG. 4 is a view which is viewed from the direction of an arrow A of FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 4. In addition, in the respective drawings which are used in the following description, in order to make each member a recognizable size, the scale of each member is appropriately changed.

FIG. 1 is a block diagram showing a schematic configuration of a turbo refrigerator S1 in this embodiment.

The turbo refrigerator S1 in this embodiment is installed in a building, a factory, or the like in order to generate cooling water for air conditioning, for example. Then, the turbo refrigerator S1 in this embodiment includes a condenser 1, an economizer 2, an evaporator 3, and a turbo compressor 4, as shown in FIG. 1.

Compressed refrigerant gas X1 that is a compressed gaseous refrigerant is supplied to the condenser 1. Then, the condenser 1 is a member which generates refrigerant liquid X2 by cooling and liquefying the compressed refrigerant gas X1. As shown in FIG. 1, the condenser 1 is connected to the turbo compressor 4 through a flow path R1, in which the compressed refrigerant gas X1 flows, and connected to the economizer 2 through a flow path R2, in which the refrigerant liquid X2 flows. In addition, at the flow path R2, an expansion valve 5 for decompressing the refrigerant liquid X2 is provided.

The economizer 2 is a member which temporarily stores the refrigerant liquid X2 decompressed in the expansion valve 5. The economizer 2 is connected to the evaporator 3 through a flow path R3, in which the refrigerant liquid X2 flows, and connected to the turbo compressor 4 through a flow path R4, in which a gas-phase component X3 of the refrigerant generated in the economizer 2 flows. In addition, at the flow path R3, an expansion valve 6 for further decompressing the refrigerant liquid X2 is provided. Also, the flow path R4 is connected to the turbo compressor 4 so as to supply the gas-phase component X3 to a second compression stage 22 which is included in the turbo compressor 4 and will be described later.

The evaporator 3 is a member which cools a cooling object such as water or the like by evaporating the refrigerant liquid X2, thereby taking heat of vaporization away from the cooling object. The evaporator 3 is connected to the turbo compressor 4 through a flow path R5, in which refrigerant gas X4 that is generated by evaporation of the refrigerant liquid X2 flows. In addition, the flow path R5 is connected to a first compression stage 21 which is included in the turbo compressor 4 and will be described later.

The turbo compressor 4 is a member which compresses the refrigerant gas X4, thereby converting the refrigerant gas X4 to the compressed refrigerant gas X1. This turbo compressor 4 is connected to the condenser 1 through the flow path R1, in which the compressed refrigerant gas X1 flows, and connected to the evaporator 3 through the flow path R5 in which the refrigerant gas X4 flows, as described above.

In the turbo refrigerator S1 having the above-described configuration, the compressed refrigerant gas X1 supplied to the condenser 1 through the flow path R1 is liquefied and cooled by the condenser 1, thereby converting the compressed refrigerant gas X1 to the refrigerant liquid X2.

The refrigerant liquid X2 is decompressed by the expansion valve 5 when being supplied to the economizer 2 through the flow path R2. Then, the refrigerant liquid X2 is temporarily stored in the economizer 2 in a decompressed state and then further decompressed by the expansion valve 6 when being supplied to the evaporator 3 through the flow path R3. Then, the refrigerant liquid X2 is supplied to the evaporator 3 in a further decompressed state.

The refrigerant liquid X2 supplied to the evaporator 3 is evaporated by the evaporator 3, thereby converting the refrigerant liquid X2 to the refrigerant gas X4, and then supplied to the turbo compressor 4 through the flow path R5.

The refrigerant gas X4 supplied to the turbo compressor 4 is compressed by the turbo compressor 4, thereby converting the refrigerant gas X4 to the compressed refrigerant gas X1, and supplied again to the condenser 1 through the flow path R1.

In addition, the gas-phase component X3 of the refrigerant generated when the refrigerant liquid X2 is stored in the economizer 2 is supplied to the turbo compressor 4 through the flow path R4. Then, the gas-phase component X3 is compressed together with the refrigerant gas X4 and then supplied to the condenser 1 through the flow path R1 as the compressed refrigerant gas X1.

Then, in the turbo refrigerator S1 having the above-described configuration, cooling or refrigeration of the cooling object is performed by taking heat of vaporization away from the cooling object when the refrigerant liquid X2 evaporates in the evaporator 3.

Subsequently, the turbo compressor 4 having characteristic portions of this embodiment will be described in more detail. FIG. 2 is a horizontal cross-sectional view of the turbo compressor 4 in this embodiment.

As shown in FIG. 2, the turbo compressor 4 in this embodiment includes a motor unit 10, a compressor unit 20, and a gear unit 30.

The motor unit 10 includes a motor 12 which has an output shaft 11 and is a driving source for driving the compressor unit 20, and a motor casing 13 which surrounds the motor 12 and in which the motor 12 is installed. In addition, the driving source which drives the compressor unit 20 is not limited to the motor 12 and, for example, an internal combustion engine is also acceptable.

The output shaft 11 of the motor 12 is rotatably supported by a first bearing 14 and a second bearing 15, which are fixed to the motor casing 13.

The compressor unit 20 includes the first compression stage 21 which inhales and compresses the refrigerant gas X4 (refer to FIG. 1), the second compression stage 22 which further compresses the refrigerant gas X4 compressed in the first compression stage 21 and then discharges it as the compressed refrigerant gas X1 (refer to FIG. 1), and a rotating shaft 23 extending over the first compression stage 21 and the second compression stage 22.

The first compression stage 21 includes a first impeller 21 a (an impeller), which provides velocity energy with the refrigerant gas X4 that is supplied from the thrust direction, and then discharges the refrigerant gas X4 in the radial direction, a first diffuser 21 b which compresses the refrigerant gas X4 by converting the velocity energy provided with the refrigerant gas X4 by the first impeller 21 a into pressure energy, and a first scroll chamber 21 c which leads the refrigerant gas X4 compressed by the first diffuser 21 b to the outside of the first compression stage 21. The first diffuser 21 b and the first scroll chamber 21 c are formed by a first impeller casing 21 e which surrounds the first impeller 21 a.

The first impeller 21 a is fixed to the rotating shaft 23. Then, the first impeller 21 a is rotated by transmitting the rotative power of the motor 12 to the rotating shaft 23.

Also, the first compression stage 21 includes a flow rate adjustment unit 40 which adjusts the flow rate of the refrigerant gas X4 which is introduced into the first impeller 21 a. The flow rate adjustment unit 40 is fixed to the first impeller casing 21 e in an airtight manner. Also, the flow rate adjustment unit 40 has an intake port 41 for the refrigerant gas X4. The intake port 41 penetrates toward the axial direction of the rotating shaft 23.

Here, the flow rate adjustment unit 40 of this embodiment will be described in more detail. FIG. 3 is a horizontal cross-sectional view of the flow rate adjustment unit 40 in the present embodiment. Also, FIG. 4 is a view which is viewed from the direction of an arrow A of FIG. 3. In addition, for explanation, in FIG. 3, the first impeller 21 a and the rotating shaft 23 are represented by an imaginary line.

As shown in FIGS. 3 and 4, the flow rate adjustment unit 40 includes a flow rate adjustment section 42, a driving section 43, a power transmission shaft 44, and an intake frame 45 (a frame).

The flow rate adjustment section 42 is a member which adjusts the flow rate of the refrigerant gas X4 (refer to FIG. 1) which is introduced into the first impeller 21 a, and has a plurality of vanes 42 a, which are blade members. The plurality of vanes 42 a is rotatably provided at a vane frame 42 b formed into an approximately circular shape, and disposed side by side in the circumferential direction at the inner circumferential surface side of the vane frame 42 b. The inner circumferential surface side of the vane frame 42 b forms a portion of the intake port 41. For this reason, the plurality of vanes 42 a rotates in synchronization with each other, whereby the apparent area from the upstream side of the intake port 41 is adjusted. In addition, the vane frame 42 b is fixed to the intake frame 45 by a plurality of screw members 42 c.

A driving-side crank arm 42 d is fixed to one of the plurality of vanes 42 a. The driving-side crank arm 42 d is provided at the outer circumferential surface side of the vane frame 42 b and connected to the power transmission shaft 44. Also, the driving-side crank arm 42 d is connected to a driving ring 42 f through a driving-side rod 42 e. The driving-side crank arm 42 d has an arm portion which protrudes in a direction intersecting the rotation axis of the driving-side crank arm 42 d, and the driving-side rod 42 e is connected to the arm portion.

The driving ring 42 f rotates the plurality of vanes 42 a in a synchronized manner, is formed into an annular shape, and is provided to surround the vane frame 42 b. The driving ring 42 f is rotatably provided at the outer circumferential surface side of the vane frame 42 b through a plurality of rolling elements 42 g.

Also, the driving ring 42 f is connected to each of a plurality of driven-side crank arms 42 i through each of a plurality of driven-side rods 42 h. The driven-side crank arm 42 i has an arm portion which protrudes in a direction intersecting the rotation axis of the driven-side crank arms 42 i, and the driven-side rod 42 h is connected to the arm portion. The plurality of vanes 42 a is respectively fixed to the plurality of driven-side crank arms 42 i.

The driving section 43 is a motor which generates power for driving the flow rate adjustment section 42. The driving section 43 is fixed to the intake frame 45 through a bracket 46. At the driving section 43, a second output shaft 43 a (an output shaft) which outputs the power of the driving section 43 is provided to protrude therefrom. In addition, the driving section 43 is not limited to a motor and for example, a driving section using hydraulic pressure or pneumatic pressure is also acceptable.

The power transmission shaft 44 is a shaft member for transmitting the power generated by the driving section 43 to the flow rate adjustment section 42. The end portion on the driving section 43 side of the power transmission shaft 44 is connected to the second output shaft 43 a of the driving section 43 through a connection plate 46 a (a connection section) which is provided in the bracket 46.

On the other hand, the end portion on the flow rate adjustment section 42 side of the power transmission shaft 44 is connected to the driving-side crank arm 42 d, as described above. In addition, in the driving-side crank arm 42 d, a hole portion for connection is formed and the power transmission shaft 44 is inserted into the hole portion for connection, thereby being connected to the driving-side crank arm 42 d. Also, in order to make the power transmission shaft 44 be engaged with the driving-side crank arm 42 d around the axis of the power transmission shaft 44, a key member 44 a is fixed to the end portion on the flow rate adjustment section 42 side of the power transmission shaft 44 and a groove portion corresponding to the key member 44 a is formed in the hole portion for connection of the driving-side crank arm 42 d.

The intake frame 45 is provided to surround the flow rate adjustment section 42 and is a member for fixing the flow rate adjustment section 42 or the driving section 43 to the first impeller casing 21 e (refer to FIG. 2). In the intake frame 45, an opening portion 45 a (an intake port) which forms a portion of the intake port 41 is formed. Also, the intake frame 45 is provided in an annular shape to surround the flow rate adjustment section 42 and also has an outer diameter which is reduced as it becomes more distant from the first impeller 21 a. For this reason, compared to a case where the intake frame 45 is formed into, for example, a cylindrical shape, the intake frame 45 is reduced in size and made lighter in weight.

In the intake frame 45, a hole portion 45 b, in which the power transmission shaft 44 is provided passing through, is formed. That is, the power transmission shaft 44 is provided by passing through the hole portion 45 b so as to come into contact with the hole portion 45 b and connects the flow rate adjustment section 42 and the driving section 43, which are respectively provided inside and outside the intake frame 45.

In the case of assembling the flow rate adjustment section 42 and the power transmission shaft 44, the power transmission shaft 44 can be connected to the flow rate adjustment section 42 by passing the power transmission shaft 44 through the hole portion 45 b before the intake frame 45 in which the flow rate adjustment section 42 is installed is fixed to the first impeller casing 21 e. That is, it is possible to assemble the flow rate adjustment section 42 and the power transmission shaft 44 while checking a connection place of the driving-side crank arm 42 d of the flow rate adjustment section 42 and the power transmission shaft 44 from the outside. For this reason, the power transmission shaft 44 to which the key member 44 a fixed can be easily inserted into the hole portion for connection of the driving-side crank arm 42 d. Accordingly, the assembly workability of the flow rate adjustment section 42 and the power transmission shaft 44 is improved.

In addition, the power transmission shaft 44 and the second output shaft 43 a are connected to each other by the connection plate 46 a and the driving section 43 is fixed to the intake frame 45 through the bracket 46. Since the above-mentioned connection and fixing can be easily performed, work to fix the driving section 43 to the intake frame 45 may be performed either before or after the intake frame 45 is fixed to the first impeller casing 21 e.

In order to prevent the refrigerant gas X4 from flowing out to the outside through the hole portion 45 b, the flow rate adjustment unit 40 includes a packing 45 c (a seal member), which keeps in an airtight manner the hole portion 45 b, in which the power transmission shaft 44 is provided passing through, between the power transmission shaft 44 and the bracket 46. As the packing 45 c, for example, a V-packing can be used.

The intake frame 45 has a flange portion 45 d. Then, the intake frame 45 is fixed to the first impeller casing 21 e by screw members (not shown) which are provided to penetrate the flange portion 45 d. Also, in order to keep a connection portion between the flange portion 45 d and the first impeller casing 21 e in an airtight manner, an annular flange packing 45 e is provided at the flange portion 45 d.

In addition, an oil thrower plate 47 is provided at the flow rate adjustment unit 40 and the oil thrower plate 47 is fixed to the vane frame 42 b of the flow rate adjustment section 42. The oil thrower plate 47 is a member that prevents a lubricant of a mist shape, which flows into the inside of the intake frame 45 through a pressure equalizing tube (not shown) connecting the intake frame 45 and an oil tank 34 (refer to FIG. 2) which will be described later, from flowing to the first impeller 21 a side.

Returning to FIG. 2, the second compression stage 22 includes a second impeller 22 a which provides velocity energy with the refrigerant gas X4 that is compressed in the first compression stage 21 and then supplied from the thrust direction, and then discharges the refrigerant gas X4 in the radial direction, a second diffuser 22 b which compresses the refrigerant gas X4 by converting the velocity energy provided with the refrigerant gas X4 by the second impeller 22 a into pressure energy and then discharges it as the compressed refrigerant gas X1, a second scroll chamber 22 c which leads the compressed refrigerant gas X1 discharged from the second diffuser 22 b to the outside of the second compression stage 22, and an introduction scroll chamber 22 d which introduces the refrigerant gas X4 compressed in the first compression stage 21 into the second impeller 22 a.

In addition, the second diffuser 22 b, the second scroll chamber 22 c, and the introduction scroll chamber 22 d are formed by a second impeller casing 22 e which surrounds the second impeller 22 a.

The second impeller 22 a is fixed to the rotating shaft 23 so as to face the first impeller 21 a. Then, the second impeller 22 a is rotated by transmitting the rotative power of the motor 12 to the rotating shaft 23.

The second scroll chamber 22 c is connected to the flow path R1 (refer to FIG. 1) for supplying the compressed refrigerant gas X1 to the condenser 1 and supplies the compressed refrigerant gas X1 derived from the second compression stage 22 to the flow path R1.

In addition, the first scroll chamber 21 c of the first compression stage 21 and the introduction scroll chamber 22 d of the second compression stage 22 are connected to each other through an external piping (not shown) which is provided separately from the first compression state 21 and the second compression stage 22. Then, the refrigerant gas X4 compressed in the first compression stage 21 is supplied to the second compression stage 22 through the external piping. The above-described flow path R4 (refer to FIG. 1) is connected to the external piping, so that the gas-phase component X3 of the refrigerant generated in the economizer 2 is supplied to the second compression stage 22 through the external piping.

The rotating shaft 23 is rotatably supported by a third bearing 26 which is fixed to the second impeller casing 22 e in a space 25 between the first compression stage 21 and the second compression stage 22, and a fourth bearing 27 which is fixed to the gear unit 30 side of the second impeller casing 22 e.

The gear unit 30 is a member for transmitting the rotative power of the motor 12 to the rotating shaft 23 and includes a spur gear 31 which is fixed to the output shaft 11, a pinion gear 32 which is fixed to the rotating shaft 23 and also engaged with the spur gear 31, and a gear casing 33 which houses the spur gear 31 and the pinion gear 32.

The spur gear 31 has a larger outer diameter than the pinion gear 32. Then, by cooperation of the spur gear 31 and the pinion gear 32, the rotative power of the motor 12 is transmitted to the rotating shaft 23 such that the number of rotations of the rotating shaft 23 increases with respect to the number of rotations of the output shaft 11. In addition, it is not limited to the above-described transmission method and the diameters of a plurality of gears may be set such that the number of rotations of the rotating shaft 23 is equal to or less than the number of rotations of the output shaft 11.

The gear casing 33 is formed separately from the motor casing 13 and the second impeller casing 22 e. Then, the gear casing 33 is a member which connects the motor casing 13 and the second impeller casing 22 e. In the inside of the gear casing 33, a housing space 33 a for housing the spur gear 31 and the pinion gear 32 is formed.

Also, at the gear casing 33, the oil tank 34, in which a lubricant that is supplied to sliding portions of the turbo compressor 4 is collected and stored, is provided.

Subsequently, an operation of the turbo compressor 4 in this embodiment will be described.

First, the rotative power of the motor 12 is transmitted to the rotating shaft 23 through the spur gear 31 and the pinion gear 32. Then, the first impeller 21 a and the second impeller 22 a of the compressor unit 20 are rotated.

When the first impeller 21 a rotates, the intake port 41 of the flow rate adjustment unit 40 is made to be in a negative pressure state, so that the refrigerant gas X4 flows from the flow path R5 into the first compression stage 21 through the intake port 41.

At this time, by adjusting the flow rate of the refrigerant gas X4 by the flow rate adjustment unit 40, the compression performance of the turbo compressor 4 and the cooling and refrigeration performance or the like of the turbo refrigerator S1 can be adjusted. More specifically, first, the driving section 43 operates, so that the second output shaft 43 a and the power transmission shaft 44 are rotated. By the rotation of the power transmission shaft 44, the driving-side crank arm 42 d is rotated, so that one vane 42 a fixed to the driving-side crank arm 42 d rotates. Also, by the rotation of the driving-side crank arm 42 d, the driving ring 42 f which is connected to the driving-side crank arm 42 d through the driving-side rod 42 e is rotated. By the rotation of the driving ring 42 f, the plurality of driven-side crank arms 42 i which is connected to each other through the plurality of driven-side rods 42 h is rotated, so that the vanes 42 a respectively fixed to the driven-side crank arms 42 i are also rotated. In this way, the plurality of vanes 42 a are rotated in synchronization with each other by the operation of the driving section 43, so that the apparent area from the upstream side of the intake port 41 can be adjusted. Accordingly, the flow rate of the refrigerant gas X4 which passes through the intake port 41 can be adjusted by the operation of the driving section 43.

The refrigerant gas X4 which has flowed into the inside of the first compression stage 21 by passing through the intake port 41 flows into the first impeller 21 a from the thrust direction and is then discharged in the radial direction with the velocity energy provided by the first impeller 21 a.

The refrigerant gas X4 discharged from the first impeller 21 a is compressed by conversion of the velocity energy into the pressure energy by the first diffuser 21 b.

The refrigerant gas X4 discharged from the first diffuser 21 b is led to the outside of the first compression stage 21 through the first scroll chamber 21 c.

Then, the refrigerant gas X4 led to the outside of the first compression stage 21 is supplied to the second compression stage 22 through the external piping (not shown).

The refrigerant gas X4 supplied to the second compression stage 22 flows into the second impeller 22 a from the thrust direction through the introduction scroll chamber 22 d and is then discharged in the radial direction with the velocity energy provided by the second impeller 22 a.

The refrigerant gas X4 discharged from the second impeller 22 a is further compressed by conversion of the velocity energy into the pressure energy by the second diffuser 22 b, thereby converting the refrigerant gas X4 to the compressed refrigerant gas X1.

The compressed refrigerant gas X1 discharged from the second diffuser 22 b is led to the outside of the second compression stage 22 through the second scroll chamber 22 c.

Then, the compressed refrigerant gas X1 led to the outside of the second compression stage 22 is supplied to the condenser 1 through the flow path R1.

With that, the operation of the turbo compressor 4 is ended.

According this embodiment, it is possible to assemble the flow rate adjustment section 42 and the power transmission shaft 44 while checking a connection place of the driving-side crank arm 42 d of the flow rate adjustment section 42 and the power transmission shaft 44 from the outside, so that the assembly workability of the flow rate adjustment section 42 and the power transmission shaft 44 is improved. Accordingly, the labor hours and cost involved in the manufacturing of the turbo compressor 4 and the turbo refrigerator S1, which are provided with the flow rate adjustment section 42 and the power transmission shaft 44 according to the present invention, can be reduced.

Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, the present invention is not limited to such an example. The shapes, combination, or the like of the respective constituent members shown in the above-described example is one example and various changes can be made on the basis of a design request or the like within the scope which does not depart from the gist of the present invention.

For example, the intake frame 45 in the above-described embodiment has an outer diameter which is reduced as it becomes more distant from the first impeller 21 a. However, it is not limited to the above-described configuration and the intake frame 45 may be formed into, for example, a cylindrical shape.

Also, the turbo compressor 4 in the above-described embodiment is used in the turbo refrigerator S1. However, the turbo compressor 4 in the above-described embodiment may be used as, for example, a supercharger which supplies compressed air to an internal combustion engine. 

1. A turbo compressor comprising: a flow rate adjustment section which adjusts the flow rate of gas that is introduced into an impeller; a driving section which drives the flow rate adjustment section; and a power transmission shaft which transmits power that is generated by the driving section to the flow rate adjustment section, wherein the turbo compressor further includes a frame which is provided to surround the flow rate adjustment section, and the frame has an intake port for gas that is introduced into the impeller and a hole portion in which the power transmission shaft is provided passing through.
 2. The turbo compressor according to claim 1, wherein the frame is provided in an annular shape to surround the flow rate adjustment section and has an outer diameter which is reduced as it becomes more distant from the impeller.
 3. The turbo compressor according to claim 1, further comprising: a connection section which connects an output shaft which outputs the power of the driving section and the power transmission shaft.
 4. The turbo compressor according to claim 2, further comprising: a connection section which connects an output shaft which outputs the power of the driving section and the power transmission shaft.
 5. The turbo compressor according to claim 1, further comprising: a seal member which keeps the hole portion, in which the power transmission shaft is provided passing through, in an airtight manner.
 6. The turbo compressor according to claim 2, further comprising: a seal member which keeps the hole portion, in which the power transmission shaft is provided passing through, in an airtight manner.
 7. The turbo compressor according to claim 3, further comprising: a seal member which keeps the hole portion, in which the power transmission shaft is provided passing through, in an airtight manner.
 8. The turbo compressor according to claim 4, further comprising: a seal member which keeps the hole portion, in which the power transmission shaft is provided passing through, in an airtight manner.
 9. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 1 as the compressor.
 10. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 2 as the compressor.
 11. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 3 as the compressor.
 12. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 4 as the compressor.
 13. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 5 as the compressor.
 14. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 6 as the compressor.
 15. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 7 as the compressor.
 16. A turbo refrigerator comprising: a condenser which cools and liquefies a compressed refrigerant; an evaporator which cools a cooling object by evaporating the liquefied refrigerant, thereby taking heat of vaporization away from the cooling object; and a compressor which compresses the refrigerant evaporated in the evaporator and then supplies the compressed refrigerant to the condenser, wherein the turbo refrigerator is provided with the turbo compressor according to claim 8 as the compressor. 